More than 100 people were left homeless early Tuesday after a massive sinkhole opened, rupturing gas and electric lines and undermining the foundation of two apartment buildings in

Hanover Township, Northampton County.

Officials made residents evacuate so quickly from the Bridle Path Woods Apartments and Townhouses that they had time to gather only bare essentials in the pre-dawn darkness.

Suresh Rajan and his family gathered clothes and forgot his 1-year-old baby's medicine. Moretta Frankel put on her clothes and shoes and grabbed her make-up. "I forgot my medicine," Frankel said hours after the evacuation began at 3:56 a.m.

The sinkhole is about 60 feet wide and about 10 feet deep, said Adam Kaplan, one of the complex's owners from Kriegman & Smith, a property management firm headquartered in Roseland, N.J.

Robert Vidoni, another owner, said a water main was repaired last month near where the sinkhole opened. But Vidoni said he isn't sure if the water main break or last weekend's rain storms caused the hole.

Residents were first evacuated to Hanover Township Volunteer Fire Company on Stoke Park Road. But with the apartment buildings deemed uninhabitable, they were taken to the Hanover Township Community Center, according to the American Red Cross of the Greater Lehigh Valley.

Red Cross spokeswoman Janice Osborne said the firehouse is around the corner from a Wegmans supermarket, so she asked the store to help feed the evacuees.

"Wegmans donated all the food," Osborne said. "All this would not be possible if it were not for Lehigh Valley donors."

The complex is just over the Bethlehem border along a secluded, wooded stretch of Bridle Path Road. Forty-eight of its 120 units are off limits, said Township Manager John J. Finnigan Jr. He said the sinkhole weakened the foundations.

Finnigan said residents called 911 to report a gas odor. Emergency crews and the complex's maintenance staff discovered the sinkhole in a grassy courtyard between two apartment buildings. Residents were evacuated, and utility crews capped the gas lines and shut off other power to part of the complex.

Finnigan said the complex's owners have hired geologists and structural engineers to determine what caused the sinkhole, the extent of the damage and the cost of repairs. But with any sinkhole, he said, finding a cause may be difficult.

"It's like what came first, the chicken or the egg," Finnigan said. "What came first, the broken water main or the sinkhole."

Sinkholes form when water dissolves porous underground limestone. The process, which can take decades or centuries, can be speeded up through leaky pipes, heavy rain and development, among other natural and man-made factors.

The National Weather Service said 1.46 inches of rain fell over the weekend, further soaking ground already saturated from the wettest February on record.

"Heavy rains and water leaks go right through the limestone bedrock," said Vidoni, the complex's co-owner.

Rajan has lived in Apartment A7 since December. He said he and his father, Soundar, who is here on vacation from India, evacuated at 4:30 a.m.

"We just took our clothes," Rajan said. "When we came out, there was a strong gas smell."

Rajan and his father went to stay at his sister's house in Downingtown, Chester County. Rajan left his son Rajun at his sister's house so he and his father could try to retrieve the baby's medicine. They were still waiting to do that late Tuesday afternoon.

Mary Banahene took the evacuation in stride. She said her neighbors called her just before 4 a.m. to tell her about the leak and that she had to leave her apartment of 13 years.